Well this is exactly what sucks about duality and life in general. Even though duality has the most potential that does not mean it is the easiest to start, in fact it is one of the more difficult type of relationships to start. This is largely due to duals being in opposite clubs, in which one's dual is mixed in with their superegos/conflictors which may cause to someone to make the mistake of believing it is best to avoid members of their opposite club altogether. The other reason for this is that duals are unlikely to meet because their fields of activity are very distant from one another. For example, an NT may spend most of his time on the internet while an SF would be doing things like going to community events. Even when you do manage to get into close contact with your dual you might think they are too good for you or that there is some sort of catch.